I been doing this way for years. Its not rocket science.
Here is the temp and time scale i use for most of my sausage making. I use this for chubs and sticks. Please note that YOUR RESULTS MAY VARY.
Outside weather conditions can also have a big part of how long it takes the meat to target IT.
TRY NOT TO EXCEED SMOKER TEMPS OF 175
I do not use a meat probe while smoking, the probe can cause fat cavitation and give false readings. Use a Thermapen to check IT of meat from the top of the chubs down thru the middle.. I know that opening the door is going to increase your time, just the nature of the game.
Hang your stuffed casings at room temp for 2 hours to dry and set. Have your smoker pre heated at 130* I use a TSM 30lb Digital smoker. Keep your top vent open. Closing the vent off will increase moisture inside your smoker and give you an unpleasant discoloration on your product. Remember this is sausage, not dripping prime rib.
1. Hang in smoker at 130* for 2 hours (no smoke)
2. 140* for 1.5-2 hrs smoke (Use of a water pan is your call)
3. 150* for 2.5 hrs (smoke opt)
4. 160 for 2.5-3 hrs (smoke opt) check meat IT here from the top of the chubs. You may have a stall in this time period.
5. Increase smoke temp to 170* (opt smoke) For 3-4 hrs. Check IT again, You should be close to your target IT of 152.
6. If you dont have time to do a complete smoke you can use hot water to finish to your IT. DO NOT EXCEED A WATER TEMP OF 170 AND MOVE THE CHUBS/STICKS AROUND IN THE WATER. Cold water bath after your IT is up to you.
NOTE: You can pull the sausage from the smoker at an IT of between 149-151 and hang at room temp. IT will IT to 152 on its own. (NO COLD WATER ON THIS WAY)